The prevalence of obesity, even in infants and children, has been increasing in the US. Obesity through childhood and into adulthood is a consistently identified risk factor for a number of chronic diseases, including many cancers. Although the obesiogenic environment is often cited as a key determinate for early childhood obesity, children differ in their vulnerability to the environment. Research on self-regulation capacities may shed light on why some children are more susceptible to an increased risk for excess energy intake and subsequent obesity. Although the self-regulatory components believed to influence risk for early childhood obesity could themselves be influenced by socio-environmental factors (e.g., parenting), there is growing evidence that they are heritable and have associations with genetic predisposition. Unfortunately, studies of candidate genes, the socio-environment or their additive affects have not produced consistent robust findings. Epigenetic mechanisms could be underlying self regulation capacities that influence health outcomes. The objective here is to: 1) determine the association that self-regulation capacities have on early childhood caloric intake and weight, and 2) identify epigenetic marks associated with these self-regulation phenotypes. This preschool study will synchronize with a newly established birth cohort, Newborn Epigenetic STudy (NEST), from which we will recruit a subset of 400 mothers and their children between the ages of 3 and 5. Data on self-regulation capacities will be collected from parent report questionnaires. Indicators of self-regulatory ability such as attention, impulse regulation, and inhibitory control will be associated with DNA methylation profiles at sequences regulating select brain-expressed imprinted genes that have been characterized from cord blood lymphocytes and buccal cells collected at birth. Genome-wide methylation profiles for ~450,000 CpG will be evaluated in relations to behavioral phenotypes. The data generated will be of high scientific value to our understanding of the basic mechanisms underlying the development of self-regulation relevant to adverse health outcomes. Such knowledge is necessary to further advance our understanding of how individual difference factors contribute to vulnerability to obesity in our modern obesiogenic environment. PUBLIC HEALTH RELEVANCE: Self-regulation failures, such as impulsivity, could make some children vulnerable to obesity. A better understanding of the types of self-regulation failures relevant to childhood obesity, as well as the underlying basic mechanism leading to these self-regulation failures could enhance prevention and treatment efforts. This study will clarify the association that self-regulation capacities have with childhood obesity as well as determine the degree to which epigenetic changes acquired prenatally are associated with the development of these self-regulatory capabilities. Knowledge generated from this study will contribute to our understanding of basic mechanisms of self-regulation and its influence on early childhood obesity.